Merge pull request #1097 from uronce-cc/lru-clean-up

[TACHYON-599] Cleanup LRUEvictor after using narrowed view

servers/src/main/java/tachyon/worker/block/evictor/LRUEvictor.java

@@ -109,12 +109,12 @@ private StorageDirView selectDirWithRequestedSpace(long bytesToBeAvailable,
    * tier, they will be evicted, otherwise, only blocks to be freed in the bottom tier will be
    * evicted.
    *
-   * this method is only used in {@link #freeSpace(long, tachyon.worker.block.BlockStoreLocation)}
+   * this method is only used in {@link #freeSpaceWithView}
    *
    * @param bytesToBeAvailable bytes to be available after eviction
    * @param location target location to evict blocks from
    * @param plan the plan to be recursively updated, is empty when first called in
-   *        {@link #freeSpace(long, tachyon.worker.block.BlockStoreLocation)}
+   *        {@link #freeSpaceWithView}
    * @return the first StorageDirView in the range of location to evict/move bytes from, or null if
    *         there is no plan
    */
@@ -139,8 +139,8 @@ private StorageDirView cascadingEvict(long bytesToBeAvailable, BlockStoreLocatio
           if (block.getBlockLocation().belongTo(location)) {
             int tierAlias = block.getParentDir().getParentTier().getTierAlias();
             int dirIndex = block.getParentDir().getDirIndex();
-            dirCandidates.add(mManagerView.getTierView(tierAlias).getDirView(dirIndex),
-                blockId, block.getBlockSize());
+            dirCandidates.add(mManagerView.getTierView(tierAlias).getDirView(dirIndex), blockId,
+                block.getBlockSize());
           }
         }
       } catch (IOException ioe) {
@@ -187,31 +187,7 @@ private StorageDirView cascadingEvict(long bytesToBeAvailable, BlockStoreLocatio
   public EvictionPlan freeSpaceWithView(long bytesToBeAvailable, BlockStoreLocation location,
       BlockMetadataManagerView view) throws IOException {
     mManagerView = view;
-    return freeSpace(bytesToBeAvailable, location);
-  }
 
-  /**
-   * This method should only be accessed by {@link freeSpaceWithView} in this class.
-   * Frees space in the given block store location.
-   * After eviction, at least one StorageDir in the location
-   * has the specific amount of free space after eviction. The location can be a specific
-   * StorageDir, or {@link BlockStoreLocation#anyTier} or {@link BlockStoreLocation#anyDirInTier}.
-   * The view is generated and passed by the calling {@link BlockStore}.
-   *
-   * <P>
-   * This method returns null if Evictor fails to propose a feasible plan to meet the requirement,
-   * or an eviction plan with toMove and toEvict fields to indicate how to free space. If both
-   * toMove and toEvict of the plan are empty, it indicates that Evictor has no actions to take and
-   * the requirement is already met.
-   *
-   * @param availableBytes the amount of free space in bytes to be ensured after eviction
-   * @param location the location in block store
-   * @return an eviction plan (possibly with empty fields) to get the free space, or null if no plan
-   *         is feasible
-   * @throws IOException if given block location is invalid
-   */
-  private EvictionPlan freeSpace(long bytesToBeAvailable, BlockStoreLocation location)
-      throws IOException {
     List<Pair<Long, BlockStoreLocation>> toMove = new ArrayList<Pair<Long, BlockStoreLocation>>();
     List<Long> toEvict = new ArrayList<Long>();
     EvictionPlan plan = new EvictionPlan(toMove, toEvict);